Two public discussions are scheduled Thursday on costs and environmental impacts stemming from the shutdown of the San Onofre Nuclear Generating Station.

The San Onofre Community Engagement Panel is holding a Thursday evening workshop in Oceanside to discuss cost estimates and environmental evaluations associated with the decommissioning of San Onofre. The twin-reactor power plant in northern San Diego County was retired in June 2013 because of the rapid degradation of newly installed steam generators.

Plant operator Southern California Edison is preparing to submit to federal safety regulators its post-shutdown decommissioning activities report, a detailed road map to dismantling the plant and restoring the coastal site that has been leased from the U.S. Navy.

A representative from the Nuclear Regulatory Commission will discuss government oversight of cost estimates and environmental assessments.

Separately, consumer advocates will gather Thursday afternoon at the Mission Valley Library in San Diego to discuss their opposition to a proposed agreement on how to divide leftover nuclear plant costs between utility customers and corporate stockholders.

The California Public Utilities Commission is considering a proposal that would charge Southern California utility customers about $3.3 billion in plant costs and unrecovered investments. Consumer advocates who brokered the agreement say it reduces by $1.4 billion potential charges by plant owners Southern California Edison and San Diego Gas & Electric. SDG&E owns a 20 percent stake in the plant.

The settlement unfairly favors utility investors, according to Ray Lutz, representing the Coalition to Decommission San Onofre, and former San Diego city attorney Mike Aguirre — hosts of the library gathering.

They organized the event after the utilities commission declined to hold a public meeting in San Diego on the settlement proposal. Members of the commission listened to public comments in Costa Mesa in June.

Customer funding for the dismantling of the plant, a process expected to last two decades, have been set aside over the years in a separate trust.